Transparent shaving cream



United States Patent TRANSPARENT SHAVING CREAM GeorgeM. Naimark, (Zleveland, Ohio No Drawing. Applicatiouseptember 30, 1953 Serial No. 383,395

1 Claim. (Cl. 167-85) This invention relates to a shaving preparation and particularly to a shaving cream of the brushless type taking the form of a spreadable jelly that is transparent in color-and therefore especially useful to a person having facial blemishes of a kind that should be avoided in shaving.

Shaving creams of the types known to the prior art are usually formulated as solutions or suspensions of soaps, although they frequentlycontain numerous other ingredients. In general, shaving preparations of the lathering type make use, among other things, of soluble and semi-soluble salts of fatty acids dissolved or dispersed inwater or at least in an aqueous vehicle. In brushless shaving preparations, on the other hand, the physical nature of the composition is usually that of an emulsion. sense transparent and, in consequence, skin blemishes are not revealed but concealed with the result that the razor is too often brought into inadvertent contact with them.

One of the'principa'l objects of the present invention is to provide a shaving cream of the 'brushless type that is transparent or water-white in color, thus permitting of its application to and use'on the face without regard to the location of skin blemishes and permitting of easy trimming of side-burns, mustaches, goatees and the like. A further object of the invention is to provide ashaving cream taking the form of a sprea'tlable je'lly that has beard-softening properties, is readily soluble in water, and may easily be rinsed from razor, hands and'face. Other objects and vadvantages of the invention will be apparent from the description which follows, which sets forth representative formulae for transparent shaving creams of the kind to which the invention relates.

A suitable formula for making a transparent shaving cream is the following, in which the concentrations, expressed in terms of percentages by weight, areapproximate:

Percent Sodium carboxymethyl cellulose (technical .grade) 2.5-3.5 Glycerol 5.0 Butyl parahydroxybenzoate 0.025 Perfume n q. :s. Water q. s.

Propylene glycol i550 Methyl parahydroxybenzoate 0.15 Wetting agent 0.5 Perfume q. s. Water In neither case is the preparation in any 2 A third formulation giving a water-white jelly suitable for use as a .brushless shaving cream is as follows:

Percent- Sodiumcarboxymethyl cellulose (pharmaceutical grade) n. 2.0 to 3.0 Glycerol 10.0 Butyl parahydroxybenzoate 0.025 Wetting agent 0.5 Perfume q. s. Water n q. s.

Still a fourth formulation for a .spreadable jelly .of this kind is shown below:

, Sodium carboxymethyl cellulose (technical or pharmaceutical grade) 1.5 to 3.5 D-sorbitol 10.0 Chlorobutanol 0.5 Wetting agent 0.5 Perfume q. s. Water q. s.

carboxyalkyl cellulose eth'ers maybe considered as, for

example, potassium carboxymethyl cellulose, potassium carboxyethyl cellulose, sodium :carboXyethyl cellulose, and the corresponding 'prop'yl and :butyl compounds.

Alkali carboxymethyl cellulose xethers 'of the kinds best meeting the requirements of the invention have, in

general, an average substitution of "about 0.7 alkali can boxymethyl radicals .for each .anhydroglucose .unit .of the cellulose structure, although the degree of substitution can vary considerably from'this level and .may in some instancestgovas high as 213.

With sodium carboxyme'thylrcelluloseof approximately 0.7 substitution, the ether will ordinarily be of the high viscosity type if the concentration :is to be :in :the range from 1.5% to 3.5%. in such=case, a 1% solution in water (by weight) should ordinarily :have'a viscosity from about 1300 to :about 2200centipoises when measured at 25 C. with a rotatingspindle viscometer of the Brookfield type. At higher'concen'tr'ations, 'l'lOWCVSLClhfilS of middle and low viscosity types may heused.

Alkali carboxyalkylacelluloses :of the kinds described have a pronounced aiiinity-forwater. Although they are mixtures rather :than pure compounds,'=they dissolve readily to form what appear'to be crystal-clear solutions' The latter are more accurately described 'ascoiloidal suspensions in'whichino discreteparticles are visible to the naked eye. "In describing them, it is usual to referito them as solutions, particularly :since the addition of more water, as in rinsing, disperses ;them with unusual rapidity. As a'result of this property,-ashaving cream formulated as hereinabove' described will be found 'to disappear promptly from irazor, hands and face when. subiected to rinsing.

The humectant; occurringin :the preparation'a's but a minor fraction but nevertheless in an :amount which, by

weight, is several times that of the sodiurn'carboxymetliyl cellulose, may vary from something :below 5% 'tosoinething above 10% Sby WBlgiJtOffthE'; preparation asia whole. It is added for the most part to keep the shaving preparation from drying on the face; however, to some extent it does have an emollient action. When a humectant is present along with Water, sodium carboxymethylcellulose Percent and a wetting agent, the resulting combination, if used as a shaving preparation, has a tendency to soften the beard after the natural oils have once been removed, as

.by a preliminary washing. In general, a greatmany of the skin. An example, is the polyoxyethylene sorbitan 1 monolaurate product supplied by the Atlas Powder Company under the trademark Tween 20. Such an ingredient, if'used, will tend to improve not only the wetting properties but also thespreading properties, beard-softening tendency and what may be called the rinsability of the preparation as a whole. The normal concentration of the wetting agent will usually range between 0.5 and 1.5 ,although it may be more or less.

Depending somewhat onthe concentration of the sodium carboxymethyl cellulose, a preservative may or may not be necessary from a theoretical standpoint, but as a practical matter one will usually be present. In general, solutions containing less than 4% of sodium carboxymethyl cellulose are susceptible to attack by bacteria, resulting in .a lowering of the viscosity. Mold growth may occur even in more concentrated solutions which are storedwfor, long periods: of time. Therefore, to inhibit mold and bacteria growth, it is advantageous to add a preservative of a kind that can be safely employed upon normal skin, as, for example, methyl parahydroxybenzoate, propyl parahydroxybenzoate, butyl parahydroxybenzoate, sodium benzoate, potassium benzoate, chlorobutanol and, to the extent that they are soluble in water, other generally similar preservatives. Preservatives of kinds known to be toxic are of course to be avoided.

preparation, although the preferred range is usually between-2.5% and 3.5%. Notwithstanding the fact that it is present in such a smallamount, the ether contributes the viscosity which gives the jelly-like character to the preparation. Ethers of the kinds described tend somewhat to lower the surface tension of water, although this lowering is not ordinarily so significant as to preclude the desirability ofadding the wetting agent. At certain concentrations, solutions of sodium earboxymethyl cellulose sometimes tend t0.ShOW thixotropic characteristics: if present, this tendency may give the shaving preparation a temporary stiffness which will not preclude its easy applicationto the face.

Both technicaland purified (99%) grades of sodium carboxymethyl cellulose may be used, although with the former precautions sometimes have to be taken in processing to improve the clarity and avoid a tendency to graininess in the product.

The pH of the final preparation should preferably be upwards of 6, as .in the range between 6 and: 9, but preferably about 7. In this'bracket, preparations of the kind described are not irritating .to normal skin,but if the pH. is permitted to go much above 9 or too far below 6 a tendency to irritation of sensitive skins may manifest itself. In this connection, it is desirable that the added ingredients, particularly the preservative, be of a nature such as not, to vary the pH unduly. In general, the pH of solutions of sodium carboxymethyl cellulose is easy to control, being ordinarily from 6 to 8.

Thus the invention provides a uniqueshaving preparation having the advantage of being limpid or, water-white stitute a complicating factor.

. d a 1 in color and permitting of use where facial blemishes con- Although taking the physical form of a colloidal suspension rather than a true solution, it is highly stable. Preparations of the kinds described are not emulsions and will not break down or discolor notwithstanding temperature changes over a wide range, although any increase in the temperature above ordinary room temperatures tends to decrease the viscosity until the temperature is reduced. An important advantage is the ease with which consistency can be controlled: slight changes in the concentration of the sodium carboxymethyl cellulose will control consistency so that the preparation will not flow from a collapsible tube with-. out pressure, will not require excessive pressure to extrude it from such a tube, and will not lose its form upon being released from the tube.

These preparations can stand for years without deleterious consequences even though in intimate contact with aluminum, tin and other metals, as in collapsible tubes and/or the common types of metal cap liners. Compounded as suggested above, the preparations have substantial lubricating properties but are so readily dispersiblc in water that they can easily be rinsed from the razor, hands and face. Being soapless, alkali-free and free of fatty acids, they are neutral or nearly and chemically inert. They are also physiologically inert; i. e., nonirritating, not toxic if taken internally, and safe if they fall into the hands of children.

It is intended that the patent shall cover, by suitable expression in the appended claim, all features of patentable novelty that reside in the invention.

What is claimed is:

A transparent shaving preparation of the 'brushless type taking the form of a water-white easily spreadable jelly consisting, in parts by weight, of 1.5% to 3.5% of a pharmaceutical grade sodium carboxymethyl cellulose of the high viscosity type characterized by a degree of hydroxyl substitution per anhydroglucose unit of less than about 1.3, 5% to 10% of a polyol selected from the group consisting of glycerol, propylene glycol and d-sorbi'tol, 0.5% of a surface-active agent having beard-softening properties, a cosmetic preservative, soluble in water, in quantity sufficient to be effective, and water as needed to make up the balance, the jelly being transparent, physiologically inert, devoid of graininess, free of any tendency to attack common metals, of a consistency such that it will not only flow from a collapsible tubeundcr pressure but will maintain its form upon being released from the tube, and characterized by a pH in the range between 6 and 9.

References Cited in the file of this patent UNITED STATES PATENTS 2,085,733 Bird July 6, 1937 2,362,761 Medl Nov. 14, 1944 2,484,637 Mattocks Oct. 11, 1949 2,550,622 Taub Apr. 24, 1951 FOREIGN PATENTS 430,248 Italy Feb; 12, 1948 OTHER REFERENCES Davies: Soap, Perfumery and Cosmetics, May I948, pp. 684-686.

Stawitz: Pharmaz. 1nd,, vol. 12, 1950, pp. 71-75.

Goldstein: J. of the Am. Pharm. Asso., vol. 14, Pharm. Ed., February 1953, pp. 111-114, 116-118.

Perfumery and Essen. Oil Record, December 1941, pp. 366 and 367.

Wallersteiner: Manufacturing Chemist, vol. 21, June 1950, pp. 238 and 239. 

